A major attack in Egypt a vital US ally on the brink of civil war soldiers reportedly opened fire on protesters -- worst violence. Since the political crisis erupted ABC's Alex mark mark is there. Good morning Paula it's being called a massacre at the attack happened right here at the Republican guard headquarters. More than forty supporters of the ousted president Mohamed -- who were killed more than 300 wounded. They say the army attacked them at dawn as they were staging a sit in -- they've been doing for the last several days. The army says they were attacked by armed terrorist. Leaving one soldier dead. This is a massive escalation of the tension here in Egypt foresees party the Muslim Brotherhood has called on its supporters to rise up. Which means there could be much more violence in the days ahead.

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Egyptian Military Clashes With Pro-Morsi Supporters

Protesters storm 6th of October Bridge in wake of president Mohammad Morsi?s removal.

Egypt Unrest: Muslim Brotherhood Calls for Protests

Supporters of ousted President Morsi release statement rejecting military coup.

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